Out of a need of Cable TV system digitalization conversion, a cable TV Cable operator in North America releases a simple set top box terminal product in a type of digital TV adapter (Digital TV Adapter, DTA), which is used to realize receiving and converting of a digital TV signal. Generally, a simple set top box product of this type has a relatively simple management manner of system control and a neat control system solution, provides an economical solution for a low-end subscriber without the necessity of a complex broadcast service, and reduces a deployment cost.
Because the system has a simple structure, and performing individual authorization management of broadcast services according to groups on each subscriber is not taken into account, the system is only capable of providing a simple service for the subscriber, and cannot realize authorization of the broadcast services according to groups. However, in a practical application, even for low-end subscribers, a difference between broadcast service demands also exists to a certain extent, and when the low-end subscriber wants to select a broadcast service, this control system that is incapable of grouping the broadcast services provided to the subscribers cannot satisfy the broadcast service grouping demand of the subscriber.